Electric clock



Jan. 14, 1941. J. A. HERNANDEZ,

ELECTRIC cn'ocx Filed Sept. 28, 1937 5 Sheets-Sheet l Jan. 14, 1941.

J.' A. HERNANDEZ ELECTRIC CLOCK Filed Sept. 28, 1937 5 Sheets-Sheet 2 Jan. 14, 194 J. A. HERNANDEZ ELECTRIC CLOCK 5 Sheets-Sheet 5 Filed Sept. 28, 1957 5? an 2 i5 0 62 Z 2 2 78 0 a 6 6 0 m a .M a w w @N r a Ylv a .H 9 I M 7 \A 4 H 7 Z M 3M M Jan. 14, 1941. I A HERNANDEZ 2,228,825

ELECTRIC CLOCK Filed Sept. 28,, 1937 5 Sheets-Sheet 4 E- 7 I 7/ g 3! M N -2/ 3A 6 37 5? 7' /0 g t. "],,mm,.

' I /2 Va Jan. 14, 1941.

J. A. HERNANDEZ ELECTRIC cLbcK Filed Sept. 28, 19:57

5 Sheets-Sheeti a r 2 25B w 1 w 5 n wm H mm m U 8 7 1 7 A .1; MM r 1 Fax M. 0 W 9 N a 9 w C 7 7 4/ N 2 l H Mm V Patented Jan. 14, 1941 UNITED STATES PATENT OFFICE Claims.

This invention relates to electric clocks, and it has for its object to provide an improved clock structure consisting in means associated with its electrically-driven mechanism, which means actuate by gravity and are connected by suitable gear means with one of the clock time indicating shafts, said means being automatically put in action when the electric current in the line that supplies the motor operating the clock falls short by any reason, so that the clock may continue to operate uninterruptedly.

Another object of the invention is to provide a mechanism for releasing the means actuating by gravity, in association with electromagnetic means in shunt relation with the electric motor in the line supplying electric energy to the latter, and which mechanism comes into action automatically when the electric current supplied to the motor fails, so that while the electric current is supplied, said electromagnetic means may retain in locked position said means actuating by gravity, and when the electric current fails, the means actuating by gravity may be released to freely actuate the usual escapement mechanism.

A further object of the invention is to provide a mechanism in an electric clock embodying such gravity actuated means which upon the resumption of the electric current supply will automatically return the gravity actuated means to its initial fully raised position.

The invention is described with reference to the figures of the accompanying drawings, of which:

Fig. 1 is a front elevational view, partly cut away, of the frame of an electric clock provided with the improvements constituting the subjectmatter of this invention.

Fig. 2 is a rear elevational view of said frame.

Fig. 3 is an upper plan view of the same frame.

Fig. 4 is a vertical sectional view on line 4-4 of Fig. 3, looking to the rear portion of the frame, in the operating position of the operating means actuating by gravity.

Fig. 5 is a horizontal view on line 5-5 of Fig. 4, in the operating position of the operating means actuating by gravity.

Fig. 6 is a vertical sectional view similar to that of Fig. 4, in the operating position of the electric means usually operating an electric clock.

Fig, '7 is a horizontal sectional view similar to Fig. 5, in the operating position of the electric operating means.

Fig. 8 is a perspective detailed view showing the oscillatable frame for releasing or holding the means actuating by gravity.

Fig. 9 is a perspective detailed view of the slidably mounted weight forming the means actuating by gravity.

Fig. 10 is a partial rear elevational view of the frame of the electric clock, showing the weight actuating by gravity and the gears connected therewith in the position in which the clock operates mechanically.

Fig. 11 is a horizontal sectional view on line HH of Fig. 10.

Fig, 12 is a similar view to Fig. 10, showing the clock when operating electrically.

Fig. 13 is a partial vertical sectional view on line l3-i3 of Fig. 7, showing the clutching slidable shaft for changing from the electric operating means to the mechanical operating means, and vice versa, in the operative position of the electric operating means.

Fig. 14 is a sectional view similar to that of Fig. 13, in the operative position of the mechanical operating means Fig. 15 is a horizontal section View on line |5l5 of Fig. 6.

Fig. 16 is a side elevational view of the clock showing the side whereon the actuating weight is mounted, in the released position thereof, when it begins to fall.

Fig. 17 is a view similar to that of Fig. 16, showing the weight in falling position, when the electric operating means have been connected again.

In Figs. 1, 2 and 3 of the drawings is illustrated an electric clock the supporting frame of which is formed by two vertical metal plates I and 2 disposed parallelly to each other and spaced apart a fixed distance by means of spacing members 3 secured by screws 3 to said plates. On the upper portion of the rear plate 2 is mounted an electric motor 4 whose horizontal driving shaft 5 extends across the plate 2 and ends in the intermediate space between plates l and 2 wherein it carries a fixed cylindrical gear wheel 6 meshing with the first gear wheel of a train of cylindrical gear wheels 1, 8 and 9 the horizontal shafts of which are rotatably mounted on an angular supporting arm I!) fixed behind the fore plate I. Although the shaft ll of the last gear wheel 9 extends to the other side of the fore plate I, it is slidably mounted through an opening in the latter and through an opening in the supporting arm ID for the purpose that will be explained hereinafter.

On the middle portion of the shaft II is fixed a cylindrical gear pinion I2 which is adapted to mesh with a cylindrical gear wheel I3 fixed on the middle portion of a horizontal shaft I4 rotatably mounted through openings in the fore plate I and rear plate 2 and on which are also fixed a cylindrical gear pinion I5 near the plate I and behind same and a small cylindrical gear wheel I6 near the plate 2 and behind same. The gear pinion I5 permanently meshes with a big cylindrical gear wheel I'I fixed on the horizontal shaft I8 rotatably mounted through the openings in the plates I and 2 and extends beyond the front of plate I whereat it carries the hands I9 and 26 on a dial not shown, so that the shaft I8 will hereinafter in this description be termed time indicating shaft. The description so far given herein is that of the structure of a usual electric clock.

This invention has for an object to provide mechanical means for actuating the time indicating shaft I8 upon failure of the current flowing in the electric line supplying power to the electric motor 4. Such mechanical means actuate by gravity and consist of a heavy metallic weight 2I slidably mounted by means of an angular groove 22 which it carries longitudinally on a slidable guide consisting of an angular flange 23 formed at the adjacent side of the rear plate 2, the flange 23 being complemental to flange 22 so that upon being engaged together they close completely one upon the other, and the weight 2I carries on its fore face an obliquetoothed rack 24 with one of whose teeth is adapted to engage a pawl 25 formed at the end of a spring 26 fixed at the other end thereof by means of screws 2'! on the inner face of the plate 2.

Normally the weight 2! is held in fixed position by said pawl '25, but immediately as current ceases to be fed to the electric motor 4, said pawl 25 is withdrawn from the rack 24 by means of a straight cam boss 28 formed on the face of a metallic strip 29 slidably mounted by means of a pair of vertical slots 30 formed therein on a pair of screws 3I horizontally fixed at vertically spaced points on the inner face of the plate 2.

Said strip 29 is pivotally connected at its upper end by means of a horizontal pin 32 with the lower end of a connecting link 33 which is pivotally connected at its upper end by means of a horizontal pin 34 with a supporting arm 35 projecting from the end of an oscillatable frame 36 oscillatorily mounted within the space between the plates I and 2 on a horizontal pivot axis 31 supported on plates I and 2. Said frame 35 is pivotally connected by means of a horizontal pin 38 passing through an opening in a lug 39 projecting upwards from an intermediate portion 40 formed on said frame 26, with the end of the forked lower portion of the movable armature M of an electromagnet 42 mounted on the top of plates I and 2 and which is connected in parallel with the electric motor 4 in the circuit formed by electric conductors 43 and 44 supplying electric current to the motor 4 from any suitable source of supply which will generally be the electric light line for a city or town.

Said oscillatable frame 36 carries on the middle portion of its side adjacent the plate 2 a downward lug 45 on which is fixed by rivets 46 a downward sheet spring 41 precisely behind the rear end of the slidably mounted shaft I I In this manner, the shaft I I will be engaged by the curved lower portion of the spring 41, when the latter descends carried by the oscillatable frame 36 (see Fig. 13) and said shaft II will be caused to run to the front until its fore end strikes against another sheet spring 48 fixed by rivets 49 on the fore face of plate I to be held in a position in which the gear pinion I2 does not mesh with the gear wheel I3 on the shaft I4 forming part of the gear mechanism transmitting motion from the electric motor 4 to the time marking shaft I8. Said oscillatable frame 36 carries also in cross alignment between the spring 4'! and its end connected to the link 33, two downward arms 50 on the lower ends of which is mounted through openings therein a horizontal counter-shaft 5| carrying a cylindrical gear pinion 52 adapted to mesh with the gear wheel I3 and a cylindrical gear wheel 53 adapted to mesh with a small cylindrical gear wheel 54 forming part of the usual escapementmechanism in clocks and which is mounted within a casing 55 fixed to the plate I at its side opposite the heavy weight 2| and which is designed to control the operation of the clock marking shaft I8 when the action of the electric motor 4 ceases. The downward movement of the oscillatable frame 36 is limited by a pin 36 fixed to the plates I and 2.

It is to be understood that the casing 55 encloses a clock escapement but not a clock movement.

The heavy weight 2I carries on its side adjacent the rear face of the plate 2 a vertical rack of straight teeth 58 (Figs. 10, 14, 15 and 16) with which permanently meshes a cylindrical gear wheel 51 the bushing 58 of which is idle on a horizontal spindle 59 threaded to the plate 2, and with the bushing 58 is made integral a ratchet wheel 60 with one of which teeth engages a pawl 6! pivotally mounted by a horizontal pin 62 on the fore face of a cylindrical gear wheel (53 the bushing 64 of which is idle on the same horizontal shaft 59, the bushings 58 and 64 being held on the shaft 59 by means of a screw 65 on a washer 65, and the pawl 6I is held in engagement with one of the teeth of the wheel 62 by means of a spring 61 fixed on the fore face of the gear wheel 63. On the rear face of the plate 2 is also fixed by means of a screw 28 a support 89 which fixedly holds a horizontal threaded spindle ID on which is idle a bushing II carrying two cylindrical gear wheels, one little I2 meshing with the gear wheel 63 and a bigger one I3 meshing with the little gear wheel I6 on the horizontal shaft I4.

In view of the above explained structure, when by virtue of the descending movement of the oscillatable frame 36 carrying along with it the metal strip 29 and the cam boss 28, the latter causes the pawl 25 to withdraw from the rack 24 and releases the heavy weight 2I for descending by gravity sliding on its guide 23, the rack 56 causes to rotate very slowly on its shaft 59 the idle bushing 58 carrying the wheels 51 and 6G in the direction indicated by the arrow in Figs. 14 and 15, whereupon the wheel 63 is caused to rotate also in the same direction through the medium of the pawl BI engaging one of the teeth of the wheel 60, and this movement of wheel 63 causes rotation of the bushing II carrying the wheels I2 and "I3 in the direction inclicated by the arrow in said Figures 14 and 15.

Since the gear wheel I3 meshes fixedly with the gear wheel I6 of shaft I4, two cases may occur: firstiy, when the gear pinion I2 does not mesh with the gear wheel I3 of the shaft I4, which occurs in the limit lowest position of the oscillating frame 36, then the gear pinion 52 of the counter-shaft 5I meshes with said gear wheel I3 and in this way the escapement contained in the housing 55 is put in action to control the rotation of the time indicating shaft I8 which receives its motion from the shaft l4 through the medium of the gear pinion l and the gear wheel fixed on said shaft l8; and in the second case when the gear pinion l2 meshes with the gear wheel [3 of the shaft M, the time indicating shaft l8 rotates in the same direction by the motion transmitted from the shaft 5 of the electric motor 4, but upon the heavy weight 2| being in retained position, the system of gear wheels 12 and I3 is caused to rotate idly on the spindle 18 by the gear wheel IE on the shaft l4 receiving its motion from the shaft 5 of electric motor 4 as already explained, but even though the gear wheel 12 cause to rotate the gear wheel 63 with which it meshes, such rotation will not produce any motion at all in the system of gear wheels 68 and 51, due to that the gear wheel 83 will rotate idly on its spindle and upon it carrying along the pawl 8|, the latter will slide on the teeth of the ratchet wheel 68 by virtue of the oblique direction of the teeth.

Really, the use of the complicated gear system constituted by gear wheels 51 to T3 is due to the division of movement that is necessary in order to accomplish the longest possible period of time in the downfall of the heavy block 2| along a predetermined height, thence in the drawing is shown a gear system from Wheel 5'! to wheel 13 which is proper to cause the heavy block 2| to descend during a time of about six hours during which the supply of current to impulse the electric motor 4 may be interrupted, but anyone skilled in the art may assume that if the heavy block 2| is desired to run the whole slide distance in only half an hour for instance, the gear system may be limited to a single wheel or two wheels.

In Figs. 6, 15, 16 and 17 is shown a mechanism whose function is to cause the heavy weight 2| gradually to move back to its initial raised position, when upon having reached a low position, it is held in that fallen position by the pawl 25 when the oscillatable frame 38 is again raised by the attraction of the electromagnet 42 on its armature 4| pivotally connected with said oscillatable frame 38, upon electric current flowing again in the electric line 4844 supplying the electric motor 4. Said mechanism is composed of a lever 14 which is pivotally mounted by a horizontal pin 15 on a plain member 16 which in turn is pivoted by a pin 11 at a small angle with the vertical on an angular support 18 slightly obliquely fixed by means of a screw 19 on the inner face of plate 2, whereby the lever 14 may effect two pivotal movements, at a time, one vertically about the pivot 15 and another substantially horizontal about the pivot H. The lever 14 is pivotally connected at its end adjacent the Vertical strip 29 and by means of a horizontal pin 88 with an arm Eli ending in a pawl of bevelled end face 82 and the arm 8| is maintained as forming a straight extension of the lever l4 in the raised position of the pawl 82 through the medium of a lower pin 83 laterally projecting from a lug 84 projecting downward from the adjacent end of the lever 14, said lug 84 being connected at a point 85 to a coil spring 85 whose other end is secured to a fixed point 8? of the plate 2.

The arm 8| extends until the pawl 82 is in vertical alignment with a series of pins 88 projecting horizontally from the front of the heavy weight 2| laterally to the rack 24 and equally spaced from each other. The lever 14 is operated at like times by two rollers 89 rotatably mounted on the ends of two radial arms 98 fixed in opposite directions on the time marking shaft I8 which, if it is the horary shaft, every half hour will raise the arm 8| carrying the pawl 82 and cause the latter to engage a pin 88 and thereby the heavy weight 2| to ascend a space equal to the vertical distance between two pins 88 at the end of which ascending movement the weight 2| rests suspended by the pawl 25 constantly engaging the rack 24. Upon releasing each roller 89 the lever 74, the latter is restored to its normal position by the action of the spring 86 and during the ascending movement of the weight 2|, the pawl 82, upon leaving one pin 88, passes clear along the inner side of the immediate lower pin 88 without striking against same in virtue of the oblique bevelled cut on its end face 82, and thus it is rendered in position to engage and raise the immediate lower pin 88 when the next roller 89 engages the lever 14 and operates it to raise the arm 8| again. In this movement, the outward swinging of the lever 14 on the pivot 1! is limited by the pressure exerted thereon by a curved spring 8| which at its lower end is fixed by screws 92 to the plate 2. The descending movement of the lever 14 and arm 8| is limited by two pins 93 and 94 fixed to the plate 2 (Fig. 4).

In the lower position of the oscillatable frame 35, in order that the arm 8| and pawl 82 may not hinder the descending movement of the weight 2|, it is necessary to leave the pawl 82 out of the vertical course of the pin 88, and for that purpose the vertical strip 29 is provided at a suitable height thereon with an arched cam stop 95 projecting upwards from a point 98 on the strip 29, which stop 35 engages the arm 8| as the strip 29 descends and forces the arm to deviate outward together with the lever 14 and causes the latter to rotate on its pivot 11.

The operation of the electric clock provided with the improvements above described, is as follows: In the normal operating conditions, that is, when the electric motor 4 receives the electric current operating it from the current supply line 4344, the shaft 5 of the motor transmits its motion to the time indicating shaft l8 through the gearing system 8, l, 8, 9, I2, l3, l5 and H, and the oscillatable frame 38 is then in raised position in virtue of the attraction exerted by the electromagnet 42 receiving current from the line 43-44, on its armature 4| connected as above described to the oscillatable frame 36 and, therefore, the gear pinion 52 being separated from the gear wheel IS, the clock escapement mechanism of the casing 55 is inoperative, while the rotation of the shaft M which actuates the gearing mechanism 73, 12, and 63 does not produce any action at all on the gear mechanism 68, 51, 58, owing to the fact that the pawl SI of the wheel 83 slides on the teeth of the wheel 89 without operating it, and the heavy weight 2| is securedly maintained in its raised position by the pawl 25 which fixedly engages the rack 24.

When by any reason the flow of current in the supply line 43-44 fails, the electric motor 4 stops, the armature 4| of the electromagnet 42 is released and falls by gravity and carries along with it the oscillatable frame 38 whose fall produces three simultaneous operations: firstly, the spring 4! will engage the rear end of the shaft II and push it onwards against the fore spring 48, whereupon the gear pinion |2 will travel a certain distance and will be disengaged from the gear wheel l3; secondly, the shaft 5| will descend until the gear pinion 52 engages the gear wheel I3 and the gear wheel 53 carried by said shaft 55 engages the small gear wheel 54 of the clock escapement mechanism housed in the casing 55; and ultimately, the strip 29 will descend, whereupon the cam boss 28 formed thereon will engage the spring 26 and the pawl 25 of the latter will be disengaged from the rack 24, after which the ieavy weight 2| will be free to fall by gravity. Upon the weight 2| being released, the side rack 2 3 thereof will actuate upon the idle gear wheel 5". causing it to rotate in the direction indicated by the arrow in Fig. 12, whereupon the wheel 60 will also rotate in the same direction through the medium of the idle bushing 58 and the wheel 65 will carry with it the gear wheel 63 through the medium of the pawl 6|, thus giving the wheel system :2, i3, i6 and 13 the rotation which was formerly given from the electric motor 4 by the meshing of gear pinion l2 with gear wheel I3, whereby the rotation of the time indicating shaft E8 will not be interrupted and the rotation time of this shaft will be controlled by the clock escapement mechanism inclosed in the casing 55.

When the heavy weight 2| is in a fallen position and electric current flows again through the circuit 43-44 supplying the electric motor 4, the current flows along the coil of electromagnet 42 and the armature 42 thereof is drawn up immediately, whereupon the oscillatable frame 36 ascends and three operations are effected which are inverse to those described above, that is: in the first place, as the spring 4'! ascends with the frame 38, it releases the rear end of the shaft l l, whereupon the fore spring 48 actuates by its own resiliency and pushes the shaft l l backward, again causing the gear pinion l2 to engage the gear wheel it; in the second place, the countershaft 51 ascends together with the frame 36 and thereby the gear pinion 52 is disengaged from the gear wheel i3 and the gear wheel 53 is disengaged from the gear wheel 54 of the escapement mechanism inclosed in casing 55, in virtue of which the escapement mechanism will remain inoperative; and in the third place, upon the strip 29 ascending with the oscillatable frame 35, the cam boss 28 thereof will release the spring 29 and the pawl 25 of the latter will again engage one of the teeth of the rack 24, to fix the weight 2| in position. In these conditions, the operation of the gear wheels system 5'! and 69 will be stopped, out the wheel 53 will continue to move idly on its spindle 59 by virtue of the motion transmitted to it from the shaft 5 of the electric motor 4 through the gear wheels and pinions 6, 1, 8, 9, l2, i3, i8, 73, i2, and the pawl 6| will slide on the teeth of the wheel 60 without actuating the latter, whereupon the time indicating shaft l8 will receive its motion direct from the shaft 5 of the electric motor 4. Furthermore, in continuing the movement of the time indicating shaft 18, if this is the hour indicating axis, the two rollers 89 will alternately engage every half hour the lever Hi causing its rear portion to descend and the arm 8! to ascend until the pawl 82 thereof engages one of the pins 88 and upon pushing this pin upward it will cause the weight 21? to ascend a determined distance at the end of which the weight will be held by the pawl 25 which is constantly engaged with the teeth of the rack 24, and so on until the weight 2| reaches such a height that the oscillation of the lever I4 will not produce any effect at all thereon, due to the fact that in its ascending movement the pawl 82 will not strike any pin 88.

It is obvious that the construction details and the shape of the structure above described may be varied, without by this reason it may be considered as altered the essential character of the invention which is such as claimed hereinafter.

What I claim is:

1. In an electric clock, a time indicating shaft, an electric circuit adapted to be connected to a source .of current, an electric motor in said circuit, a train of gears for operating the time indicating shaft from the motor, electromagnetic means in said circuit including an armature, vertically oscillatable means secured to said arma ture, gravity actuated means releasably connected to said oscillatable means upon de-energization of the electromagnetic means upon failure of current, ratchet means for drivingly connecting the gravity actuated means to one of the gears of the gear train of the electric clock, a clock escapement, and gear means on the oscillatable means for driving the clock escapement from one of the gears of the gear train, whereby the clock is driven by the gravity actuated means and its motion controlled by the escapement upon failure of the current.

2. In an electric clock, a clock frame, a time indicating shaft, an electric circuit adapted to be connected to a source of current, an electric motor in said circuit, a train of shafts and gears for operating the time indicating shaft from the motor, means on the clock frame for slidably mounting one of the shafts of said shaft and gear train along its axial line, electromagnetic means in said circuit including an armature, vertically oscillatable means secured to said armature, resilient means secured to the vertically oscillatable means for disconnecting the slidable shaft of said shaft and gear train from the electric motor, gravity actuated means releasably connected to said oscillatable means upon de-energization of the electromagnetic means upon failure of current, ratchet means for drivingly connecting the gravity actuated means to the slidable shaft of said shaft and gear train, a clock escapement on the clock frame, and gear means .on the oscillatable means for driving the clock escapement from the slidable shaft of said shaft and gear train, whereby the clock is driven by the gravity actuated means and its motion controlled by the escapement upon failure of the curren 3. In an electric clock, a clock frame, a time indicating shaft, an electric circuit adapted to be connected to a source of current, an electric motor in said circuit, a train of shafts and gears for operating the time indicating shaft from the motor, an angular arm secured on the clock frame for slidably mounting one of the shafts of said shaft and gear train along its axial line, electromagnetic means in said circuit including an armature, a vertically oscillatable frame secured to said armature, a spring secured to said oscillatable frame for engaging and sliding the slidable shaft of said shaft and gear train, a spring secured to the clock frame for backing said slidable shaft upon release by the first mentioned spring, gravity actuated means releasably connected to said oscillatable frame upon de-energization of the electromagnetic means upon failure of current, ratchet means for drivingly connecting the gravity actuated means to the slidable shaft of said shaft and gear train, a clock escapement on the clock frame, and gear means on the oscillatable frame for driving the clock escapement from the slidable shaft of said shaft and gear train, whereby the clock is driven by the gravity actuated means and its motion con- .trolled by the escapement upon failure of the current.

4. In an electric clock, a clock frame, a time indicating shaft, an electric circuit adapted to be connected to a source of current, an electric motor in said circuit, a train of shafts and gears for operating the time indicating shaft from the motor, means on the cloak frame for slidably mounting one of the shafts of said shaft and gear train along its axial line, electromagnetic means in said circuit including an armature, a vertically oscillatable frame secured to said armature, a Weight slidably supported on the clock frame and releasably connected to said oscillatable frame upon de-energization of the electromagnetic means upon failure of current, ratchet means for drivingly connecting the weight to the slid alble shaft of said shaft and gear train, lever means pivortally supported on the clock frame and releasably connected to said weight upon resumption of the electric current supply, and rotatable means on the time indicating shaft which are adapted to operate said lever means, whereby the clock is driven by the weight upon failure of the current and upon resumption of the current the clock itself will automatically return the weight to its initial fully raised position.

5. In an electric clock, a clock frame, a time indicating shaft, an electric circuit adapted to be connected to a source of current, an electric motor in said circuit, a train of shafts and gears for operating the time indicating shaft from the motor, means on the clock frame for slid'ably mounting one of the shafts of said shaft and gear train along its axial line, electromagnetic means in said circuit including an armature, a vertically oscillatable frame secured to said armature, a weight slidably supported on the clock frame and releasably connected to said oscillata ble frame upon de-energization of the electromagnetic means upon failure of current, ratchet means for drivingly connecting the weight to the slidable shaft of said shaft and gear train, a series of pins projecting from the weight and spaced apart in vertical alignment, lever means pivotally supported on the clock frame, a pawl pivotally connected to one end of said lever means and adapted to ireleasably engage a pin on the weight, spring means connecting the pivotally connected end of said lever means to the clock frame, 'a pair of diametrically opposed radial arms on the time indicating shaft, and rollers rotatably mounted on the ends of said radial arms and adapted to engage the free end of said lever means, whereby the clock is driven by the weight in falling upon failure of current and upon resumption of the current the clock itself will automatically return the fallen weight to its initial fully raised position.

JOSE ANDRES HERNANDEZ. 

